AU627198B2

AU627198B2 - Continuously variable transmission

Info

Publication number: AU627198B2
Application number: AU37042/89A
Authority: AU
Inventors: Akiyoshi Morishita; Mitsunao Takayama; Kozo Yamauchi; Tsutomu Yasue
Original assignee: Aichi Machine Industry Co Ltd
Current assignee: Aichi Machine Industry Co Ltd
Priority date: 1989-05-25
Filing date: 1989-06-27
Publication date: 1992-08-20
Anticipated expiration: 2009-06-27
Also published as: US5050457A; AU630098B2; EP0405021A1; AU3704289A; CA2005074C; CA2005075A1; CA2005074A1; JPH03350A; ES2052005T3; EP0405022A1; DE68910680D1; JP2558522B2; EP0405021B1; DE68910680T2; CA2005075C; EP0405022B1; US4964841A; JPH03358A; AU3704389A; ES2048288T3

Description

P/00/011 OW1y627198 Form PATENTS ACT 1952-1973 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Class: Int. CI: Application Number: Lodged: Complete Specification-Lodged: ,TOO Accepted: 9 A Published: 'Priority: Related Art: Name of Applicant: TO BE COMPLETED BSY APPLICANT AICHI KIKAI KOGYO KABUSHIKI KAISHA, of 2-20, Kawanalni-cho, Atsuta-ku, Nagoya, Japan.

I 9 9 04 0 Address; of Applicant: Actual Inventor: *MITSUNAO TAKAYAkMA, TSUTOMU YASUE, AKIYOSHI MYORISHITA AND KOZO YAMAUCHI Address for Service: COWIE, CARTER HERY PAT1ENT WiADEMARC, AT-rORNEYS 71 QUEENS ROAD, MELBOURNE, 3004, AUSTRALIA Complete Specification for the invention entitled: CONTINUOUSLY VARIABLE TRANSMISSION The following statement is a full description of this invention, including the best method of performing it known to me:--1 *Note: The description isato be typed In double spacing, pica typo face. in an area not exceeding 250mmn In depth and 160 mm In with.

on tough white paper of good quality and it isa!o be inserted inside this foem 1171 W76-L C. J.THpwm. Comumael'h Owmmm Priaw,. Canbum q are the actual inventor(s) of the invention and the facts upon which the applicant is entitled to make the application are as follows:- The said company is the assignee of -the invention from the said actual inyentors.

CONTINUOUSLY VARIABLE TRANSMISSION BACKGROUND OF THE INVENTION Field of the invention The present invention relates to a V-shaped belt (hereinafter referred to as V belt) type continuously variable transmission.

Description of the Prior Art In general, a V belt type continuously variable transmission contains an input pulley composed of a pair of half pulleys mounted on an input pulley shaft to move axially toward and away from each other, an output pulley composed of a pair of half pulleys mounted on an output pulley shaft to move axially ji toward and away from each other, and a V belt which frictionally engages the pulleys to transmit the rotation rrom the input I; pulley shaft to the output pulley shaft to vary the rotational o0 0 speed continuously.

o* 0 The means to transmit the rotation between both pulley shafts depends upon the V belt member only in the V belt type :coO. continuously variable transmission which is actually used at present. In such a construction, there are several defects as follows; First the allowable transmission capacity is limited by the V belt strength so that the improvement of the transmission capacity and the compaction of the construction are obstructed.

Secondly when the V belt stuck into the groove between half pulleys of the output pulley shaft because the vehicle stopped suddenly and its wheels and the output pulley shaft connected to them are brought to stop, power transmitting becomes impossible. Or the drive ratio is made to the higher position so that the restart becomes difficult or the acceleration is not accomplished satisfactorily due to weak drive power.

If the movable input half pulley is forced to be moved by large power to change the drive ratio in the state of V belt stuck, the pulley or V belt is damaged.

When the V belt is cut away, it goes without saying that the vehicle becomes impossible to operate.

TO overcome those defects, countermeasures have been proposed in which a sub power transmitting path is provided a in addition to the power transmitting path with the V belt so that either one of them selectively transmits its output power through a hydraulic clutch or the like to the wheels in compliance with the drive ratio.

The above proposed construction, however, still has the following problems. i 0- First switching the paths is accompanied by shock.

Secondly two clutches are required at least to switch respective output from each power transmitting path so that the construction becomes large size with great weight and high j 0 production cost, and controlling of the system tends to be complicated.

Thirdly condition of sliding malfunction or sticking of V belt is apt to be irregular so that appreciating the condition 2i .r _i is difficult and effective recovery action is not performed.

Furthermore, in a V belt type continuously variable transmission of this kind, as shown in FIG.16, one input half pulley B of a pair of input half pulleys B, C mounted on a input pulley shaft A is made to move axially along the input pulley shaft and the position of the input half pulley B is controlled by a half pulley position control D operated through an actuator not shown. The half pulley position control D contains an outer slider E to be rotatably operated by the actuator and an inner slider F to be engaged through screw with the outer slider E which supports the rear end of the input movable half pulley B. Consequently, when the outer slider E moves toward and away 0 along the input pulley shaft through the actuator, the input ooo .oo* movable half pulley B is moved to be controlled in its position.

o o In such conventional V belt type continuously variable S0 transmission, however, the axial load due to the V belt H during operation is directly added to the power transmitting members of the actuator such as a bearing G, an outer slider E, so that C 00 those members, for instance the bearing G, are damaged or great operating power is necessary for the actuator.

000 SUMMARY OF THE INVENTION An object of the present invention is to provide a V belt type continuously variable transmission having a main power 0 o transmitting path and a sub power transmitting path for transmitting driving power toward the output pulley shaft through both paths according to engine operating conditions in order L- to increase driving power and accelerating force and also to decrease load to be added to the V belt.

Another object of the present invention is to provide a V belt type continuously variable transmission having a 2-way differential clutch for switching the forward and backward rotation transmitted, through the sub power transmitting path so that the construction and controlling are simplified and weight of the continuously variable transmission is decreased because of saving numbers of clutches to be required.

A further object of the present invention is to provide a V belt type continuously variable transmission having a 2-way differential clutch for switching the forward and backward o rotation transmitted through the sub power transmitting path so that assembly of the V belt type continuously variable

Q

oo, 1 transmission can be easily performed.

A still further object of the present invention is to C provide a V belt type continuously variable transmission having a main power transmitting path and a sub power transmitting path for transmitting cooperatively driving power toward the .4 output pulley shaft through both paths at the range near the ao maximum drive ratio so that the sufficient driving power and accelerating force can be gained during low speed operation wherein the great torque is required and further the load to 0 oV the V belt can be decreased. Furthermore, such a V belt type continuously variable transmission has the advantage that switching the rotational direction can be easily performed at 4 i :L C -F shifting the selector and that the damage or sticking of the V belt can be smoothly recovered. I; A still further object of the present invention is to provide a V belt type continuously variable transmission having a drive ratio control with simplified construction.

A still further object of the present invention is to provide a V belt type continuously variable transmission having a half pulley position control in which the axial force acting on members of the actuator through the movable input half pulley can be decreased so that improvement of the life of the actuator members, decrease of the driving torque through the actuator, and smooth shifting of the drive ratio become possible.

The foregoing objects of the invention are accomplishing by providing a V belt type continuously variable transmission comprising: main power transmitting path means including an input pulley mounted on an input pulley shaft, an output pulley mounted on an output pulley shaft and a V belt frictionally engaged between said input and said output pulley, each of said input pulley and said output pulley comprising a pair of half pulleys, one of said half pulley of said input pulley being stationarily mounted to said input pulley shaft and the other of said half pulley of said input pulley being slidably mounted to said input pulley shaft so as to move toward and away from said stationarily mounted half pulley for continuously varying the rotational speed of said output pulley shaft relative to the rotational speed of said input pulley shaft; S.. sub power transmitting path means distinct from said main power transmitting path |i means for transmission of rotation of said input pulley shaft to said output pulley shaft, and '1 control means for performance of cooperative power transmission by said main transmitting path means and said sub power transmission path means, said control means being composed of a 2-way differential clutch provided in said sub power transmission path means.

The 2-way differential clutch is preferably mounted on a countershaft disposed between the input pulley shaft and output pulley shaft.

NB-37042.spc I 1 C" 0 d O~r) e d 0

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D

-6- BRIEF DESCRIPTION OF THE DRAWINGS The objects and features of the invention may be understood with reference to the following detailed description of an illustrative embodiment of the invention, taken together with the accompanying drawings in which: Fig. 1 is a diagrammatic illustration of an entire construction of a V belt type continuously variable transmission.

Fig. 2 is an enlarged side elevation view, partly in half cross section, of a movable half pulley position control of the input pulley shown in Fig. 1.

Fig. 3 is a sectional view taken along line III-III in Fig. 2.

Fig. 4 is a side sectional view of a 2-way differential clutch shown in Fig. 1.

Fig. 5 is a sectional view taken along line V-V in Fig. 4.

Fig. 6 is an enlarged sectional view of the relevant parts shown in Fig. Fig. 7 is an enlarged sectional view similar to that of -3742.s I T' FIG.6 in the different operational condition.

FIG.8 is a flow chart of controlling by the drive ratio control.

FIG.9 to FIG.14 are characteristic diagrams in respective results of controlled position of the movable input half pulley in several shift conditions in relation to load parameters on the main and sub power transmitting paths.

is a characteristic diagram in the relation between axial forces of the movable input half pulley vs. drive ratios of the V belt type continuously variable transmission shown 00 0 °0 o:0 in FIG.2 and 3 compared to those of the prior art.

FIG.16 is a side elevation view, partly in half cross 0 00 0000 section, of relevant parts of a conventional V belt type 0 continuously variable transmission.

00 00 DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG.1, there is shown a V belt type °0 continuously variable transmission in which the output shaft of a prime mover E such as an internal combustion engine 0 0.

is coaxially connected to a main drive shaft 14 through a clutch 12. The end of the main drive shaft 14 is also coaxially 044 connected to a input pulley shaft 18 through a bearing 16.

Parallel to the main drive shaft 14 and the input pulley shaft 18 there is arranged a shaft 22 of a synchro-coupling for switching forward and backward movement, and a counter driven gear 24 secured to the shaft 22 engages a main drive gear 26 secured to the main drive shaft 14. Moreover the shaft 0. 7 H, 4 5ete toaiptpleysat1 hoghabaig1 s^ Paale 1 ;,~andiesat1 adteiptple !1 22 of the synchro-coupling 20 is slidably provided with a forward counter gear 28 and a backward counter gear 30 for the rotation of the shaft 22 to be transmitted while switching to forward or backward movement. The forward counter gear 28 engages No.1 pulley shaft gear 32 secured to the end of the input pulley shaft 18, while the backward counter gear 30 engages an idler gear 36 which engages No.2 pulley shaft gear 34 secured to the midway of the input pulley shaft 18.

The rest part of the input pulley shaft 18 is provided with a stationary input half pulley 38 secured thereto, a movable input half pulley 40 slidably inserted thereon, and a half pulley position control 42 to control the position of the movable input half pulley 40 in the axial direction.

Parallel to the input pulley shaft 18 there is arranged a output pulley shaft 44, which is provided with a stationary output half pulley 46 secured thereto and a movable output half pulley 48 mounted theco-n to move in the axial direction.

The stationally input half pulley 38 and movable input half pulley 40 have respective opposite conical surfaces to form a V-shaped groove 50 therebetween to thereby constitute a input pulley 52. Also the stationally output half pulley a4 46 and movable output half pulley 48 have respective opposite conical surfaces to form a V-shaped groove 56 therebetween to thereby constitute a output pulley 58. The input pulley 52 and output pulley 58 are frictionally engaged through respective V-shaped grooves 50 and 56 by a V belt 60, which causes T continuously to vary the drive ratio of the rotations between the input pulley shaft 18 and output pulley shaft 44 when the half pulley position control 42 governs the position of the movable input half pulley 40 to vary the width of the V-shaped groove Referring now to FIG.2 and 3 t:here is shown the construction of the half pulley position control 42. In FIG.2, the end of input pulley shaft 18 is provided with a bearing 52, which supports an inner slider 66 integrally having cylindrical portion 66a with male screw. The inner slider 66 is fixed with pins t 70 to a case 68, partly shown in FIG.2, covering the front area eooo of the movable input half pulley 40, the case 68 which is mounted on a stationary part not shown. The cylindrical portion 66a 06 t with male screw extends axially along the input pulley shaft O0 o 18 with appropriate clearance to engage cylindrical portion 72a with female screw of the outer slider 72 which is rotated o clockwise or counterclockwise by an actuator not shown.

The front side portion of th, movable input half pulley 40 is integrally formed with a cylindrical portion 40a, which is connected to the cylindrical portion 72a with female screw *o of the outer slider 72 through a bearing 74 relatively to rotate |1 and axially to move together.

The input pulley shaft 18 is provided with an annular roller L holder 76 with a C ring 78 within the cylindrical portion of the movabl.e. input half pulley 40. On the radially outer end of the roller holder 76 there is formed a lug 76a, which AA: proj ects into a groove between a pair of proj ected stripes (refer to FIG.3) axially formed on the inner surface of the cylindrical portion 40a. Moreover the lug 76a is provided with a roller bearing 82 being in slidable contact with opposite inner surfaces of the stripes 80, 80 to make up a guide for the movable input half pulley 40 in the axial direction.

Within the cylindrical portion 40a of the movable input half pulley 40 there is inserted a compression coil spring 84 between the inner surface of a conical portion 40b and the roller holder 76 so that the movable input half pulley 40 is forced to the stationary 38 by the compression coil spring.84.

In the half pulley position control 42 described above ace the movable input half pulley 40 guided through the projected stripes 80, 80 and the lug 76a of the roller holder 76 axially moves toward the stationary input half pulley 38 to reduce the width of the V-shaped groove 50 as the outer slider 72 is rota~ted 0 in one direction by the acLuator, or the movable input half pulley 40 moves away from the stationary input half pulley 38 0 to spread the width of the V-shaped groove 50 as the slider 72 is rotated in the other direction. Moreover the movable input 00: half pulley 40 is capable of rotating together with the input pulley shaft 18 because of engagement of the projected stripes 80 and the lug 76a. In addition, the movable input half pulley 40 is always loaded in the axial forward direction or the direction in which V-shaped groove 50 is widened while the V belt 60 transmits the rotation to the output pulley 58, and L1~; i as the result the loading force acts on the supporting portion of the outer slider 72 at the front end of the cylindrical portion 40a. In the half pulley position control 42, however, such loading force is canceled by the force of the compression :coil spring 84 so that the loads to the outer slider 72 and also to the bearing 74 are reduced. Besides, the vibration of the movable input half pulley 40 mounted on the rotating shaft 18 is absorbed by the compression coil spring 84 so that noise during the operation is reduced.

Referring to FIG.15, there is shown a characteristic diagram in the relation between axial forces (kg) of the movable input oo half pulley 40 vs. drive ratios of the V belt type continuously claa o variable transmission compared to those of the prior art. In the drawing the curve A shows the characteristic of this "15 embodiment and the curve B shows that of the prior art. In this case the change of the load by the compression coil spring 0000 I 0 84 is shown with the curve C in the drawing. It will be

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appreciated that the significant effect of axial force reduction is obtained in this embodiment comparing to the prior art.

Referring to FIG.1 again, there is shown a countershaft °j i'a 86 disposed between the input pulley shaft 18 and the output j \pulley shaft 44, the countershaft 86 which is provided with a 2-way differential clutch 88.

Referring now more. particularly to FIG.4 to 7 in detail, the countershaft 86 has several stepped forms on the peripheral surface. On a stepped part of the countershaft 86 there is l IT d slidably mounted an input gear 90 through spline 90a. Teeth are formed on the peripheral of the input cpar 90 and engages a No.1 pulley shaft gear 32 of the input pulley shaft 18.

Another stepped part of the peripheral of the countershaft 86 is .provided with a polygonal cam 92 parallel to the input gear An output gear 94 is inserted on the peripheral of the polygonal cam 92 with clearance 93. Teeth 94a are formed on the peripheral of the output gear 94 and engages a driven gear 96 of the output pulley shaft 44.

Referring to FIG.6 of enlarged sectional view of the G o relevant parts, a pair of rollers 102, 102' are disposed on o the surrounding surface 98, 98', 100, 100' of double-wedge-shaped

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clearance 93 (hereinafter referred to as double-wedge-shaped surface) which is formed between the inner cylindrical surface 15 98 of the output gear 94 and the polygonal cam-shaped surface of the countershaft 86. A pair of the rollers 102, 102' are 00 respectively accommodated in a pocket 104a of a retainer 104, and a spring 106 is disposed between the rollers 102, 102' and Soo urges respective rollers 102, 102' toward the opposite walls of the pocket 104a. It will be noted that the rollers 102, I 102' in the neutral condition shown in FIG.6 do not contact VI r to any of the wedge-shaped surfaces 100, 100'.

SReferring to FIG.4, a sub gear 108 is inserted between the input gear 90 and the output gear 94. Teeth 108a are formed on the peripheral of the sub gear 108 and engages the No.1 pulley shaft gear 32 similarly to the input gear 90. Within the inner -k L u• 0

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;r -e I peripheral of the sub gear 108 the retainer 104 is slidably inserted on the peripheral of the countershaft 86. The retainer 104 and the sub gear 108 are forced to contact to each other by a disc spring 110 between an end surface of stepped portion of the countershaft 86 and a side surface of the input gear A recess 112 is formed in a part of the inner peripheral of the retainer 104 while a stopper 86a is projected on a .peripheral of the countershaft 86 in the position facing the recess 112. The countershaft 86 is supported by bearings 116 to 118.

0 44 00h e4444P 01* O 0 0 di 44 440 044 SIn the 2-way differential clutch 88 described above, the rotation of the input pulley shaft 18 is transmitted to the input gear 90 and the sub gear 108 respectively engaging No.1 pulley shaft gear 32. The numbers of tooth 90b of the input 15 gear 90 is set to be smaller than those of tooth 108a of the sub gear 108, the numbers of tooth 90b are 53 while those of tooth 108a are 54 for instance, so that the rotation of the sub gear 108 delays as compared with that of the input gear 90. Consequently, as seen in FIG.7, the retainer 104 pressed to contact with the sub gear 108 has a differential speed against the rotation of the countershaft 86 so that it relatively S rotates in the right direction until the left side surface of the recess 112 contacts with the stopper 86a. Then the right side roller 102' of a pair of rollers 102, 102' accommodated in the pocket 104a of the retainer 104 is urged to contact with the wedge-shaped surface 100', 98' by the force of the spring 1 m.l ,i i:- L i i The following statement is a full description of this invention, including the best method of performing it known to me:- -1- *Note: The decnption ito be typed in double pacing, pic type face, in an area not exceedng 250 mm n depth and 10mm n width, on tough whit paper of good quality and it ito be inerted inid this form.

11710/76-L. C J. THosoN.C CommonwlhGovmmet Prinerw. Canberra I I I I m r 106. In such condition, when the rotational speed of the output gear 94 is faster than that of the input gear 90, the roller 102' slips and does not stick to the wedge-shaped surface 100', 98'. It will be appreciated that the roller 102 does not stick to the wedge-shaped surface 100, 98 since it does not contact with the surface. On the contrary, when the rotational speed of the output gear 94 is slower than that of the input gear the rotational speed of the polygonal cam 92 becomes faster than that of the output gear 94, and then the roller 102' sticks to the wedge-shaped surface 100', 98' to thereby cause to o transmit the rotation of the countershaft 86 to the output gear oo 94. In this case, after the stopper 86a has contacted with the wall surface of the recess 112, the retainer 104 slips relatively to the sub gear 108 and as a result the sub gear 108 does not be damaged. Such wedge effect of the rollers 102, 102' due to the differential speed of the sub gear 102 is o regardless of the rotational direction of the input gear Referring to FIG.1 again, a differential pinion 120 is secured to the output pulley shaft 44 to engage an idler gear 122, which in turn engages a differential gear 126 of a Vo differential gear case 124.

t A computer 128 composed of microprocessors is input with signals from an input pulley rotational speed sensor 130 detecting the rotational speed of the input pulley 52, an output pulley rotational speed sensor 132 detecting the rotational speed of the output pulley 58, an half pulley position sensor L- I _I il- .li: 134 detecting the position of the movable input half pulley of the input pulley 52, and a sift position sensor, not shown, of the selector 136, The computer 128, depending upon those signals, controls an actuator of the outer slider 72, the actuator which moves the input pulley 52 to control it toward a position appropriate to engine operational conditions.

In the V belt type continuously variable transmission of this invention, after the output power from the prim mover E has been transmitted to the input pulley shaft 18 through the clutch 10 and the synchro-coupling 20, two paths is operable to -ansmit the output power from the input pulley shaft 18 o0 *oCO to the output pulley shaft 58. That is, two paths are a main °oIo 0 power transmitting path through a V belt engaged between the input pulley 52 and the output pulley 58 and a sub power transmitting path through the 2-way differential clutch 88.

So The drive ratio of the sub power transmitting path is set in a o a slightly smaller value than the maximum drive ratio of the main power transmitting path.

Consequently, when the movable input half pulley 40 of the output pulley 50 has been moved near the position of the o maximum drive ratio in the main power transmitting path, the i rotational speed of the output gear 94 in the 2-way differential clutch 88 become slower than that of the. input gear 90, and as a result a rotational force is given to the output gear 94 so that the output pulley shaft 44 is rotated through the sub power transmitting path in addition to the main power S: a A C11 I r r r 3 a'9 -1 :t i "r transmitting path.

Similarly according to such construction, when the selector is manipulated such as D-N-R or R-N-D, the 2-way differential clutch 88 is capable of smoothly switching the transmitting rotational direction by idling and power transmitting.

Referring to FIG.8, there is shown a flow chart of controlling the position of the input pulley 52 through the actuator by the computer 128, wherein; ia: drive ratio through the main power transmitting path VSPD: rotational speed of the output pulley shaft 58 TVO: throttle valve open position of the carburetor QQ FLG RNG: condition flag due to range, vehicle speed ooo* FLG R: flag of R or not FLG selective flag during R 15 I: Lowmax IS: vehicle speed reference (I15 118) S° I16: target ratio correction 0 16b I18: vehicle speed reference Firstly, evaluate shift position in Step a. When shift position is D, N, then go to Step b, and when R, go to Step c. Evaluate condition flag FLG RNG due to range and vehicle *'oU speed in Step b. When flag is 0, go to Step d. When flag is 1, then go to Step e. And when flag is 2, then go to Step f.

Evaluate FLG R 0 in Step d. When YES, go to Step e, and when NO, go to Step f. Evaluate VSDP 1I15 in Step f. When YES, go to Step g, where put FLG RNG 2, and go to Step h, where

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i i- -s i b- 1 PL Ll^rilii i_ put ia 1 I16. When NO, go to Step i, where put FLG RNG 0, FLG R 1, and FLG RS 0. Then go to Step j, where get ia which is determined from VSPD and TVO according to normal control.

Evaluate VSPD S I18 in Step e. When YES, go to Step k, where put FLG R 1 and go to Step g. When NO, go to Step 1, where put FLG RNG 1 and go to Step h.

And put FLG RNG 0 and FLG R 0 in Step c. Then go to Step m, where evaluate VSPD 115. When YES, go to Step n, where put FLG RS 0. Then go to Step o, where put ia Il.

o" When NO, go to Step p, where put FLG RS 1 and go to Step h.

BReferring to FIG.9 to FIG.14, there are shown respective ".Poo results of controlled position of the movable input half pulley o in several shift conditions in relation to load parameters on the main and sub power transmitting paths.

The V belt type continuously variable transmission according to the present invention is sufficiently operative in the following particular cases during the operation. That is, for o' instance, if the V belt 60 is cut away, the output power is capable of being transmitted to the output pulley shaft 44 S* through the 2-way differential clutch 88 in the sub power transmitting path. Similarly, if V belt 60 is stuck into the output pulley 58 due to sudden stop of the vehicle, the stick of V belt 60 can be recovered and smooth restart of the engine is accomplished because even if the drive ratio is in high speed side when the restarting, it can be varied to the low speed r

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side or the maximum drive ratio, and simultaneously the rotation is transmitted to the output pulley shaft 44 through the 2-way differential clutch 88 in the sub power transmitting path.

7 7 44 0 0 0@ 4 44 9944 4 4406 4940 9 .4 6A~0 49 6 4 4+4 44* 44 00 4 4 0044 o 40 64 0 .4 94 04 4 494 9 44 1

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00 041 4~4 4 &141

Claims

1. A V belt type continuously variable transmission comprising: main power transmitting path means including an input pulley mounted on an input pulley shaft, an output pulley mounted on an output pulley shaft and a V belt frictionally engaged between said input and said output pulley, each of said input pulley and said output pulley comprising a pair of half pulleys, one of said half pulley of said input nulley being stationarily mounted to said input pulley shaft and the other of said half pulley of said input pulley being slidably mounted to said input pulley shaft so as to move toward and away from said stationarily mounted half pulley for continuously varying the rotational speed of said output pulley shaft relative to the rotational speed of said input pulley shaft; sub power transmitting path means distinct from said main power transmitting path means for transmission of rotation of said input pulley shaft to said output pulley shaft, and control means for performance of cooperative power transmission by said main transmitting path means and said sub power transmission path means, said control means 15 being composed of a 2-way differential clutch provided in said sub power transmission path means.

2. The V belt continuously variable transmission as defined in claim 1 wherein said 2-way differential clutch is mounted on a countershaft which is disposed between said input pulley shaft and said output pulley shaft. DATED this 9th day of June, 1992. AICHI KIKAT KOGYO KABUSHIKI KAISHA CARTER SMITH BEADLE Qantas House 2 Railway Parade Camberwell 3124 Victoria Australia A.nJ. u NB-37042.spc OL r-